ABSTRACT Alzheimer's Disease and its Related Dementias (AD/ADRD) are brain diseases whose immense human and societal costs and burdens represent an increasingly urgent public health need; moreover, over 90% of patients with AD/ADRD exhibit neuropsychiatric symptoms (e.g., depressive symptoms, psychosis, agitation) for which there are currently no approved therapies?pointing to the importance of research on the neuropsychiatric correlates and sequelae of AD/ADRD. This administrative supplement request is premised on the fact that the rationale for and unmet needs targeted in the scope and aims of the parent grant can be even more effectively met (i.e. not changed but enriched) by adding AD/ADRD to the other two broad categories of disorders in the parent grant (mental illness and addictions). By extending the broad disease categories and voices from the affected stakeholder groups in Aims 1 and 2 to include cutting-edge AD/ADRD research (e.g., research involving novel drugs, devices, or mechanisms to examine the underlying neurobiology, disease progression, and therapeutic avenues in AD/ADRD) and stakeholders in AD/ADRD research, the Aims and Scope of the parent grant remain unchanged, while the real-world application and impact of the products from the parent grant are substantially enhanced. Current and future BRAIN Initiative studies will yield novel tools, methods, technologies, and treatments that will undoubtedly be used in AD/ADRD research. Therefore, it is crucial to examine the ethical dimensions not only of mental illness and addiction related innovative neuroscience, but also of AD/ADRD research that involves innovative, BRAIN Initiative-driven or -inspired science. Our two Supplemental Aims incorporate AD/ADRD into the first two Specific Aims of the parent R01. In Supplemental Aim 1, we will use semi-structured interviews and qualitative methods to articulate ethical issues in highly innovative neuroscience research related to AD/ADRD by interviewing professional and lay stakeholders. In Supplemental Aim 2, survey items and vignettes, informed by Supplemental Aim 1 data, will be used to examine factors influencing research decision making by people with AD/ADRD and/or their family members/caregivers in the context of innovative neuroscience research. These Supplemental Aims will readily fold into the timeline of our existing parent project (see Project Timeline), as we have developed efficient and effective recruitment strategies for Aims 1 and 2 of the parent R01. This Supplement efficiently leverages our existing R01 to facilitate additional ethical inquiry focused on AD/ADRD research. The conceptual model we are examining in our existing R01 (i.e., the Roberts Ethical Valence model) provides a novel basis for ethics inquiry in the domain of AD/ADRD research. By layering AD/ADRD research ethics questions onto our existing R01 approach, we will be able to achieve richer and more robust comparisons across types of disorders (i.e., mental illnesses such as depression and schizophrenia; addiction; AD/ADRD; physical illness; healthy comparison subjects), as well as across professional and lay stakeholder groups.